/* scandir: Scan a directory, collecting all (selected) items into a an array.

 *

 * This code borrowed from 'libit', which can be found here:

 *

 * http://www.iro.umontreal.ca/~pinard/libit/dist/scandir/

 *

 * The original author put this code in the public domain.

 * It has been modified slightly to get rid of warnings, etc.

 *

 * Below is the email I received from pinard@iro.umontreal.ca (François Pinard)

 * when I sent him an email asking him about the license, etc. of this

 * code which I obtained from his site.

 *

 * I think the correct spelling of his name is Rich Salz.  I think he's now 

 * rsalz@datapower.com...

 * -- 

 * Rich Salz, Chief Security Architect

 * DataPower Technology                           http://www.datapower.com

 * XS40 XML Security Gateway   http://www.datapower.com/products/xs40.html

 *

 *	Copyright(C):	none (public domain)

 *	License:	none (public domain)

 *	Author:		Rich Salz <rsalz@datapower.com>

 *

 *

 *

 *	-- Alan Robertson

 *	   alanr@unix.sh

 *

 **************************************************************************

 *

 * Subject:	Re: Scandir replacement function

 * Date:	18 May 2001 12:00:48 -0400

 * From:	pinard@iro.umontreal.ca (François Pinard)

 * To:		Alan Robertson <alanr@unix.sh>

 * References:	1

 *

 *

 * [Alan Robertson]

 *

 * > Hi, I'd like to use your scandir replacement function found here:

 * > http://www.iro.umontreal.ca/~pinard/libit/dist/scandir/ But, it does

 * > not indicate authorship or licensing terms in it.  Could you tell me

 * > who wrote this code, under what license you distribute it, and whether

 * > and under what terms I may further distribute it?

 *

 * Hello, Alan.  These are (somewhat) explained in UNSHAR.HDR found in the

 * same directory.  The routines have been written by Rick Saltz (I'm not

 * completely sure of the spelling) a long while ago.  I think that nowadays,

 * Rick is better known as the main author of the nice INN package.

 *

 **************************************************************************

 *

 * I spent a little time verifying this with Rick Salz.

 * The results are below:

 *

 **************************************************************************

 *

 * Date: Tue, 20 Sep 2005 21:52:09 -0400 (EDT)

 * From: Rich Salz <rsalz@datapower.com>

 * To: Alan Robertson <alanr@unix.sh>

 * Subject: Re: Verifying permissions/licenses/etc on some old code of yours -

 *  scandir.c

 * In-Reply-To: <433071CA.8000107@unix.sh>

 * Message-ID: <Pine.LNX.4.44L0.0509202151270.9198-100000@smtp.datapower.com>

 * Content-Type: TEXT/PLAIN; charset=US-ASCII

 *

 * yes, it's most definitely in the public domain.

 *

 * I'm glad you find it useful.  I'm surprised it hasn't been replaced by,

 * e.g,. something in GLibC.  Ii'm impressed you tracked me down.

 *

 *	/r$

 *

 * -- 

 * Rich Salz                  Chief Security Architect

 * DataPower Technology       http://www.datapower.com

 * XS40 XML Security Gateway  http://www.datapower.com/products/xs40.html

 * ---------------------------------------------------------------------->

 * Subject:	scandir, ftw REDUX

 * Date: 	1 Jan 88 00:47:01 GMT

 * From: 	rsalz@pebbles.bbn.com

 * Newsgroups:  comp.sources.misc

 *

 *

 * Forget my previous message -- I just decided for completeness's sake to

 * implement the SysV ftw(3) routine, too.  

 *

 * To repeat, these are public-domain implementations of the SystemV ftw()

 * routine, the BSD scandir() and alphasort() routines, and documentation for

 * same.  The FTW manpage could be more readable, but so it goes.

 *

 * Anyhow, feel free to post these, and incorporate them into your existing

 * packages.  I have readdir() routiens for MSDOS and the Amiga if anyone

 *  wants them, and should have them for VMS by the end of January; let me

 *  know if you want copies.

 *

 *                        Yours in filesystems,

 *                                /r$

 *

 *                                Anyhow, feel free to post

 * ----------------------------------------------------------------------<

 *

 */

#include <crm_internal.h>

#include <sys/types.h>

#include <dirent.h>

#include <stdlib.h>

#include <stddef.h>

#include <string.h>

#ifndef NULL

#  define NULL ((void *) 0)

#endif

/* Initial guess at directory allocated.  */

#define INITIAL_ALLOCATION 20

int

scandir(const char *directory_name,

        struct dirent ***array_pointer, int (*select_function) (const struct dirent *),

#ifdef USE_SCANDIR_COMPARE_STRUCT_DIRENT

        /* This is what the Linux man page says */

        int (*compare_function) (const struct dirent **, const struct dirent **)

#else

        /* This is what the Linux header file says ... */

        int (*compare_function) (const void *, const void *)

#endif

    );

int

scandir(const char *directory_name,

        struct dirent ***array_pointer, int (*select_function) (const struct dirent *),

#ifdef USE_SCANDIR_COMPARE_STRUCT_DIRENT

        /* This is what the linux man page says */

        int (*compare_function) (const struct dirent **, const struct dirent **)

#else

        /* This is what the linux header file says ... */

        int (*compare_function) (const void *, const void *)

#endif

    )

{

    DIR *directory;

    struct dirent **array;

    struct dirent *entry;

    struct dirent *copy;

    int allocated = INITIAL_ALLOCATION;

    int counter = 0;

    /* Get initial list space and open directory.  */

    if (directory = opendir(directory_name), directory == NULL)

        return -1;

    if ((array = (struct dirent **)malloc(allocated * sizeof(struct dirent *))) == NULL)

        return -1;

    /* Read entries in the directory.  */

    while (entry = readdir(directory), entry)

        if (select_function == NULL || (*select_function) (entry)) {

            /* User wants them all, or he wants this one.  Copy the entry.  */

            /*

             * On some OSes the declaration of "entry->d_name" is a minimal-length

             * placeholder.  Example: Solaris:

             *      /usr/include/sys/dirent.h:

             *              "char d_name[1];"

             *      man page "dirent(3)":

             *              The field d_name is the beginning of the character array

             *              giving the name of the directory entry. This name is

             *              null terminated and may have at most MAXNAMLEN chars.

             * So our malloc length may need to be increased accordingly.

             *      sizeof(entry->d_name): space (possibly minimal) in struct.

             *      strlen(entry->d_name): actual length of the entry. 

             *

             *                      John Kavadias <john_kavadias@hotmail.com>

             *                      David Lee <t.d.lee@durham.ac.uk>

             */

            int namelength = strlen(entry->d_name) + 1; /* length with NULL */

            int extra = 0;

            if (sizeof(entry->d_name) <= namelength) {

                /* allocated space <= required space */

                extra += namelength - sizeof(entry->d_name);

            }

            if ((copy = (struct dirent *)malloc(sizeof(struct dirent) + extra)) == NULL) {

                closedir(directory);

                free(array);

                return -1;

            }

            copy->d_ino = entry->d_ino;

            copy->d_reclen = entry->d_reclen;

            strcpy(copy->d_name, entry->d_name);

            /* Save the copy.  */

            if (counter + 1 == allocated) {

                allocated <<= 1;

                array = (struct dirent **)

                    realloc_safe((char *)array, allocated * sizeof(struct dirent *));

                if (array == NULL) {

                    closedir(directory);

                    free(array);

                    free(copy);

                    return -1;

                }

            }

            array[counter++] = copy;

        }

    /* Close things off.  */

    array[counter] = NULL;

    *array_pointer = array;

    closedir(directory);

    /* Sort?  */

    if (counter > 1 && compare_function)

        qsort((char *)array, counter, sizeof(struct dirent *)

              , (int (*)(const void *, const void *))(compare_function));

    return counter;

}